More energy efficient cooling system by utilizing defrosting water

ABSTRACT

Utilizing condensing/defrosting water as additional coolant to cool the condenser coil makes cooling systems such as refrigerator, air conditioner, etc more energy efficient and reduces the possibility of condensing/defrosting water overflow from condensate collection pan. The compressed media flowing from bottom to top of the condenser coil makes more water evaporate. By introducing the working interval of cooling system makes the cooling system more energy efficient by optimally utilizing the low temperature condensing/defrosting water.

BACKGROUND OF THE INVENTION

The condensing/defrosting water generated by cooling system such as refrigerator, air conditioner, etc was captured in the collection reservoir under the bottom of the system. This water was open to atmosphere and slowly evaporated naturally or was introduced to drainage system. Heavily using the cooling system may cause excess water overflow for no drainage systems. The water has much higher heat capacity (more than 100 times of air) and high latent heat of vaporization. Using water as additional coolant to cool the condenser coil is much more efficient than air only. Therefore the present invention is to improve the cooling system more energy efficient, especially in light of ever increasing energy cost and encouraging people to use more energy efficient appliances. Additionally, it will improve the overflow problem for the cooling systems without drainage system.

SUMMARY OF THE INVENTION

Waste water generating by cooling system, such as condensing or defrosting water was introduced as additional coolant to cool the condenser coil. It not only makes the cooling system more energy efficient but also reduces the possibility of water overflow. To optimally utilize the condensing water to cool the condenser coil, it is better to have the cooling system to work in intervals which make the condensing water have more low temperature and closer to the freezing point while it reaches the condenser coil. Compressed media flowing from bottom to top of radiator will bring more heat away due to water evaporating.

BRIEF DESCRIPTION OF THE DRAWINGS

A typical cooling system in a schematic diagram. Compressed media and water flow were indicated in different arrows.

DETAIL DESCRIPTION OF THE INVENTION

While the air passes the evaporator coil the water vapor will be condensed, frozen or frosted on coil. The water vapor in a cool container will be condensed, frozen or frosted on the container wall as well. As the temperature goes up, the ice or frost will be melting to form as condensing or defrosting water. This water is then treated as waste water and is introduced to drainage system or let it evaporate slowly from collection pan. This water has the low temperature close to frozen point. Introducing this water to condenser coil makes the high temperature condenser coil have more heat exchange. Since the heat capacity of water is 100 times more than air, using this water as additional coolant will make heat exchange more efficient compared to a radiator which is only cooled by using a fan to force the environmental temperature air passing it. The water will bring away extra heat by two ways: 1) when the water temperature rise from above frozen point to environmental temperature and 2) when the water evaporate which absorb more heat based on high latent heat of vaporization of water. To utilize the waste water as additional coolant, it is required that the condenser coil must be at least lower than the evaporator coil or under the evaporator coil as shown in FIGURE. Due to the temperature gradient between the surfaces of evaporator coil and the top of frost, the temperature on the top of frost will be increased as the thickness of frost increases. To advance utilizing low temperature water the cooling system needs shut down for a short period for certain working intervals, e.g. shut down compressor 1 minute for every 10 minutes working. The compressor operating periodically can be easily controlled in the electrical box of cooling system. This procedure makes the frost on the evaporator coil melt to water and flow to the condenser coil. One benefit is water temperature is close to the frozen point when it reaches the condenser coil while the compressor starts to work again. If the shut down period is too long, the temperature of water will increases as the time passes due to water exchanges heat with others such as air, metal sheet, or plastic materials. The second benefit is to increase the cooling effect of the heat exchange with air due to less or no frost on evaporate coil. While the compressed media flow through the condenser coil, the temperature is very high in the entry and low in the exit. The high temperature of compressed media going through the condenser coil from bottom to top as shown in FIGURE makes more water evaporate from the collection pan. This improvement makes more heat exchange from both water temperature increasing and water evaporation, and it reduces the water in collection pan since more water became as water vapor. 

1. Utilize the waste water such as condensing or defrosting water as additional coolant to cool the condenser coil of a cooling system.
 2. Waste water may introduce to any level from top to bottom of condenser coil, or direct into water collection reservoir to let the condenser coil partially soak in the water.
 3. The high temperature of compressed media going through the condenser coil from bottom to top results in more water evaporating and more heat exchanged which results in more energy efficient.
 4. The working interval of the compressor varies based on the models, purposes, and loading capacity of each cooling system.
 5. Claims from 1 to 4 apply to any cooling system by using expansion of compressed media, such as refrigerator, air conditioner, etc. 